<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>类选择器</title>
    <link rel="stylesheet" href="./class.css" />
  </head>
  <body>
    <!-- #region main -->
    <h1 class="fz30">我是标题</h1>
    <p class="fz30">我是段落</p>
    <!-- #endregion main -->
    regin
  </body>
</html>
